When this nation’s founders devised a national legislature, they created two chambers: the House and Senate. Representatives from local jurisdictions would advance more parochial needs; senators would focus on broader strategic issues. The notion of internal checks and balances within the legislative branch itself helped to seal ratification of the Constitution; the House and Senate would work together as well as at cross-purposes.

What wasn’t likely envisioned was that, hundreds of years later, one senator and one congressman from an original colony would serve as counterweights in a debate that involved the Cold War, Jewish immigration, multibillion-dollar companies, and a Russian lawyer who died in his jail cell. Just a few miles apart geographically, with motivations reflecting their conscience as well as status, Massachusetts’ Senator John Kerry and Representative Jim McGovern are key actors in an episode that is as much about constitutional architecture as it is modern day realpolitik.

A vote expected in the Senate on Thursday would grant normalized trade relations with Russia and finally end the Cold War. The bill, after last month’s similar vote in the House, would revoke the 1974 ban, known as Jackson-Vanik, that penalized US-Russian economic investments because of the Soviet Union’s prohibition on emigration for Jews. Times have changed, as have global markets, and the expected Senate approval would create a permanent normal trade relationship with Russia. All this activity is in response to Russia’s entry into the World Trade Organization last August, essentially setting ground rules for foreign access to Russian industries and lowering any import tariffs; the United States doesn’t want to be left behind.

Embedded in the legislation is a narrative less about money and more about human rights. The House and Senate both have tied the trade status to justice for a Russian lawyer, Sergei Magnitsky, who was tortured and died in prison in 2009 after unearthing rampant government corruption. The legislation denies visas to the named abusers and freezes their assets. The Russian government waged an all-out war against the provisions.

Over a year ago, I wrote about the Magnitsky case and the legislative push around it. I don’t mean to sound jaded, but the death of a Russian in jail wouldn’t normally rise to the level of diplomatic gamesmanship. But Magnitsky worked for a British based hedge fund, Hermitage Capital Management, whose American-born founder Bill Browder has spent the better part of three years seeking to reveal and punish the culprits; the Russians have retaliated against Browder and even Magnitsky, filing criminal complaints against a dead man (the first time in Russian history) and a foreign citizen (only the third time).

Enter Representative McGovern, the original sponsor of the Magnitsky bill, and co-chair of the Tom Lantos Human Rights Commission. His introduction of the Magnitsky legislation annoyed Russia, whose leadership called the step “provocative” and urged the Obama administration to leave Russia’s internal affairs alone.

Enter John Kerry, whose status as chair of the Foreign Relations Committee made him a possible broker of compromise. While promoters of the Magnitsky bill refused to backtrack on their principles, opponents argued that Russian and US relations are too consequential to be defined by the death of a single lawyer.

With these dueling priorities, months passed. But the legislative process can be cunning and capable. The Magnitsky bill was linked to something that would make the Russians happy: normalized trade status.

The whole affair is nothing more than the carrot and stick approach — Kerry offering the carrot, McGovern the stick (or, as one Hill staffer told me, “Kerry as Kissinger, McGovern as Jane Fonda”). And now the Russians are fumbling a bit. They have called the Magnitsky bill “unfriendly” and have promised “responsive measures” should it pass. But, just this week, Russian officials were meeting with Wall Street executives trying to attract economic investment. Moscow explained to the US capitalists that, actually, Russia isn’t all that mad about the Magnitsky bill after all.

Or maybe the Russians are simply coming to appreciate what our framers envisioned long ago: that what is often viewed as the curse of divided government can actually work like a charm.